Rapid analysis and residue evaluation of six fungicides in grape wine-making and drying

Abstract

Rapid multianalysis methods of metalaxyl-M, boscalid, picoxystrobin, fluopicolide and its metabolite 2,6-dichlorobenzamide, pyraclostrobin, and mandipropamid in grapes, wine, and raisins were established. The residue determination of six fungicides in wine-making and fruit-drying processes and evaluation were studied. The six fungicides exhibited good linearity in all three matrices (r > 0.9953). The average recoveries of the six fungicides at three added levels were 78.8 %–106.3 % (RSD 0.6 %–12.5 %). During wine-making processes, metalaxyl-M dissipated slowly (T1/2 = 248 h), while the other five fungicides dissipated rapidly (T1/2 = 17−44 h). The transfer rates of the six fungicides in wine and pomace were 0.9 %–14 % and 22 %–72 %, respectively. During the drying process, the dissipation of metalaxyl-M was very limited, and the half-lives of the other five fungicides were 39−84 h. The processing factors (PFs) of the six fungicides during wine-making and drying were 0.01-0.19 and 0.35-0.97, respectively, which indicates that these processes can reduce the residues of these six fungicides in wine and raisins. The established multianalysis method provides a reference for the simultaneous detection of target pesticides in grape and its processed products. The residue determination results provide reasonable data for reducing pesticide residues and the dietary risk factors of grapes and their processed products.